Investments in Austin-area venture-backed companies increased 163 percent during the first quarter, rising sharply to $213.8 million compared with $81.7 million during the same period last year. Although deal volume was the exact same as the year-earlier period, 18 investments each, the median funding round amount surged from $3.8 million during the first quarter 2013 to $4.8 million this year, according to Dow Jones VentureSource. Technology companies accounted for $99 million of the total $213.8…